Screen or grating.



PATEN'IED DEC. 31, 190'?.

M. LEVY.

SCREEN 0R GRATING. APPLICATION FILED MAB. 2. 1907.

I .IMMMI aucune/11 MAX LEVY, Ol" PHILADELPHIA, PENNSYLVANIA.

SCREEN 0R GRATING.

Specification of Letters Patent.

Patented Dec. 31, 1907.

Application filed March 2, 1907. Serial No. 360.132.

To all whom it 'may concern.'

Be it known that I, MAX LEVY, a citizen of the United States, residing at Philadelphia, in the county of Philadelphiaand State of Pennsylvania, have invented certain new and useful Improvements in Screens or Gratings, of which the following is a specification.

This invention relates to improvements in screens or gratings, the purpose being to provide the same with a frame, the screen yor grating being constructed to receive the frame, such frame when attached to the lined or ruled plates )roviding a covering for the joint between tie lates, and means whereby the plates wi be held against movement one upon the other.

Screens or gratings as at present manufactured are practically fraineless, they being made up of two lined or ruled plates of glass which are cemented together, and in use such screens are liable to injury from a variety of causes, among whichmay be mentioned, a separation of theI plates adjacent to their edges, or the staining ofthe margin by reason of the entrance of acid, chemicals, or moisture to the joint. The

plates are liable to crack, especially at the corners from jars received in handling, and they are fre uently injured or broken by pressure of t e clamps used to secure the screen in position in the camera or plateholder. In hot summer weather and in rooms where the temperature is high, the plates are liable, to slide one upon the other, this isespecially the case when the screen is placed at an inclination so that the screen rests u on the edge of one of the plates, the other p ate then being supported by the Cand ada balsam which is used to connect the lined plates. The conditions under which a screen or grating is used precludes the use of a frame that extends beyond the surfaces of the glasses.

In carrying out my invention, I use lined or ruled plates which are cemented to each other with Canada balsain, and the margins of the screen 0r grating are reduced as to thickness, such reduced margins being overlaid by a frame, preferably of metal, and in practice the frame is cemented to the screen,

, all as will be hereinafter set forth.

invention. Fig. 2, is a plan view, showing a di'erent form of corner joint. Fig. 2a, is a section of the form of frame shown by Fig. 2. Fig. 3, is a detail perspective View of one form of sheet metal frame. Figs. 4 and 5 are plan views of modified forms, Figs. 4 and 5, being sections thereof. Figs. 4" and 5b, are perspective sections of the plates. Figs. 6, 6, 6h, 7 and 8 are sectional views of other modifications of my invention.

The lined or ruled glass plates A and B which are cemented to each other in the usual manner have their opposite margins reduced or cut away to form a marginal tongue C, which is of less thickness than the combined thickness of the plates. In forming the tongues on the margins of the plates, I incidenta ly produce shoulders c, and also roughen the surface of the tongues. The shoulders and the ground surfaces are advantageous, for the shoulders as well as the edges provide bearing surfaces for the frame and the unpolished surfaces afford a better hold for the cement b, which is laced upon the tongue or in the groove ofp the frame. The cement used to produce a tight joint between the screen and frame may be Canada balsain or an asphaltic preparation. The margins of the plates may be reduced in thickness so that the tongues will have beveled surfaces as shown by Figs. 5, 5b, 7, and

'8 of the drawings.

The frame D, is preferably made of metal, and has a groove to receive the reduced margin of the screen, the depth of the groove being such that the inner edges cl of the parts of the frame that overlie the tongue will be in line with the shoulders c, and the cement is placed either in the groove in the frame or upon the reduced margin of the screen before the frame is applied.

The cement not only serves to connect the frame to the screen but also forms atight joint and allows for dierences in expansion and contraction. The corners of the frame may be either squared or mitered, and as shown the frame may be made up of one or more parts or of sheet metal bent in shape.

The corners of the screen may be initered so that the frame will not engage therewith.

Having thus set forth my invention what I claim as new, and desire to secure by Letters Patent, is:

l. The combination with a grating or screen made up of lined plates and provided with a margin of less thickness than its field,

of a frame thatncases the reduced margin of the gratingr` or screen, for the purpose set V provided With a margin of less thickness than its field, of a frame that incases the reduced margin of the grating or screen the thickness of the frame being such as not to exceed the thickness `of the lield, for the purpose set forth.

3. The combination With a ating or screerrhavin a margin of less thic ess than the y,ield o`f"`t e screen, of a frame which ncases the margin of the grating or screen and is connected t creto by cement.

4. A rating or' screen made up of lined or ruled p ates Which are cemented 'to each 420 other and provided with reduced margins,

and a rigid frame which is cemented to the margin of the-gratin or screen, the frame not exceeding in thidlmess the thickness of the grating or screen.

5. A screen or grating for use in photomechanical engraving consisting of lined or ruled glass plates Which are cemented together and provided With a marginal tongue,

in combination With a grooved frame which does not exceed in thickness the thickness of the screen or grating, and an interposed ad? In testimony Whereor1 I aflix -my signature,

jin presence of two Witnesses.

MAX LEVY.

Witnesses:

- C. A. HANssER,

E. L. WooDWARD. 

